/*
 * Object3DBranch.java 23 jan. 09
 *
 * Sweet Home 3D, Copyright (c) 2007-2009 Emmanuel PUYBARET / eTeks <info@eteks.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package com.eteks.sweethome3d.j3d;

import java.awt.Shape;
import java.awt.geom.Area;
import java.awt.geom.GeneralPath;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.WeakHashMap;

import javax.media.j3d.BranchGroup;
import javax.media.j3d.ColoringAttributes;
import javax.media.j3d.LineAttributes;
import javax.media.j3d.Material;
import javax.media.j3d.PolygonAttributes;
import javax.media.j3d.Texture;
import javax.vecmath.Color3f;

import com.eteks.sweethome3d.model.Home;
import com.eteks.sweethome3d.model.Room;

/**
 * Root of a branch that matches a home object. 
 */
public abstract class Object3DBranch extends BranchGroup
{
	// The coloring attributes used for drawing outline 
	protected static final ColoringAttributes OUTLINE_COLORING_ATTRIBUTES = new ColoringAttributes(
			new Color3f(0.16f, 0.16f, 0.16f), ColoringAttributes.FASTEST);
	protected static final PolygonAttributes OUTLINE_POLYGON_ATTRIBUTES = new PolygonAttributes(
			PolygonAttributes.POLYGON_LINE, PolygonAttributes.CULL_BACK, 0);
	protected static final LineAttributes OUTLINE_LINE_ATTRIBUTES = new LineAttributes(0.5f,
			LineAttributes.PATTERN_SOLID, true);
	
	protected static final Integer DEFAULT_COLOR = 0xFFFFFF;
	protected static final Integer DEFAULT_AMBIENT_COLOR = 0x333333;
	protected static final Material DEFAULT_MATERIAL = new Material();
	
	private static final Map<Long, Material> materials = new HashMap<Long, Material>();
	private static final Map<Home, Map<Texture, Texture>> homesTextures = new WeakHashMap<Home, Map<Texture, Texture>>();
	
	static
	{
		DEFAULT_MATERIAL.setCapability(Material.ALLOW_COMPONENT_READ);
		DEFAULT_MATERIAL.setShininess(1);
		DEFAULT_MATERIAL.setSpecularColor(0, 0, 0);
	}
	
	/**
	 * Updates this branch from the home object.
	 */
	public abstract void update();
	
	/**
	 * Returns a cloned instance of texture shared per <code>home</code> or 
	 * the texture itself if <code>home</code> is <code>null</code>.
	 * As sharing textures across universes might cause some problems, 
	 * it's safer to handle a copy of textures for a given home. 
	 */
	protected Texture getHomeTextureClone(Texture texture, Home home)
	{
		if (home == null || texture == null)
		{
			return texture;
		}
		else
		{
			Map<Texture, Texture> homeTextures = homesTextures.get(home);
			if (homeTextures == null)
			{
				homeTextures = new WeakHashMap<Texture, Texture>();
				homesTextures.put(home, homeTextures);
			}
			Texture clonedTexture = homeTextures.get(texture);
			if (clonedTexture == null)
			{
				clonedTexture = (Texture) texture.cloneNodeComponent(false);
				homeTextures.put(texture, clonedTexture);
			}
			return clonedTexture;
		}
	}
	
	/**
	 * Returns the shape matching the coordinates in <code>points</code> array.
	 */
	protected Shape getShape(float[][] points)
	{
		GeneralPath path = new GeneralPath();
		path.moveTo(points[0][0], points[0][1]);
		for (int i = 1; i < points.length; i++)
		{
			path.lineTo(points[i][0], points[i][1]);
		}
		path.closePath();
		return path;
	}
	
	/**
	 * Returns a shared material instance matching the given color.
	 */
	protected Material getMaterial(Integer diffuseColor, Integer ambientColor, float shininess)
	{
		if (diffuseColor != null)
		{
			Long materialKey = new Long(diffuseColor + (ambientColor << 24) + ((char) (shininess * 128) << 48));
			Material material = materials.get(materialKey);
			if (material == null)
			{
				Color3f ambientMaterialColor = new Color3f(((ambientColor >>> 16) & 0xFF) / 255f,
						((ambientColor >>> 8) & 0xFF) / 255f, (ambientColor & 0xFF) / 255f);
				Color3f diffuseMaterialColor = new Color3f(((diffuseColor >>> 16) & 0xFF) / 255f,
						((diffuseColor >>> 8) & 0xFF) / 255f, (diffuseColor & 0xFF) / 255f);
				material = new Material(ambientMaterialColor, new Color3f(), diffuseMaterialColor,
						new Color3f(shininess, shininess, shininess), shininess * 128);
				material.setCapability(Material.ALLOW_COMPONENT_READ);
				// Store created materials in cache
				materials.put(materialKey, material);
			}
			return material;
		}
		else
		{
			return getMaterial(DEFAULT_COLOR, DEFAULT_AMBIENT_COLOR, shininess);
		}
	}
	
	/**
	 * Returns the list of polygons points matching the given <code>area</code>.
	 */
	protected List<float[][]> getAreaPoints(Area area, float flatness, boolean reversed)
	{
		return getAreaPoints(area, null, null, flatness, reversed);
	}
	
	/**
	 * Returns the list of polygons points matching the given <code>area</code> with detailed information in 
	 * <code>areaPoints</code> and <code>areaHoles</code>.
	 */
	protected List<float[][]> getAreaPoints(Area area, List<float[][]> areaPoints, List<float[][]> areaHoles,
			float flatness, boolean reversed)
	{
		List<List<float[]>> areaPointsLists = new LinkedList<List<float[]>>();
		List<List<float[]>> areaHolesLists = new LinkedList<List<float[]>>();
		ArrayList<float[]> currentPathPoints = null;
		float[] previousPoint = null;
		for (PathIterator it = area.getPathIterator(null, flatness); !it.isDone(); it.next())
		{
			float[] point = new float[2];
			switch (it.currentSegment(point))
			{
				case PathIterator.SEG_MOVETO:
					currentPathPoints = new ArrayList<float[]>();
					currentPathPoints.add(point);
					previousPoint = point;
					break;
				case PathIterator.SEG_LINETO:
					if (point[0] != previousPoint[0] || point[1] != previousPoint[1])
					{
						currentPathPoints.add(point);
					}
					previousPoint = point;
					break;
				case PathIterator.SEG_CLOSE:
					float[] firstPoint = currentPathPoints.get(0);
					if (firstPoint[0] == previousPoint[0] && firstPoint[1] == previousPoint[1])
					{
						currentPathPoints.remove(currentPathPoints.size() - 1);
					}
					if (currentPathPoints.size() > 2)
					{
						float[][] areaPartPoints = currentPathPoints.toArray(new float[currentPathPoints.size()][]);
						Room subRoom = new Room(areaPartPoints);
						if (subRoom.getArea() > 0)
						{
							boolean pathPointsClockwise = subRoom.isClockwise();
							if (pathPointsClockwise)
							{
								// Keep holes points to remove them from the area once all points are retrieved
								areaHolesLists.add(currentPathPoints);
							}
							else
							{
								areaPointsLists.add(currentPathPoints);
							}
							
							if (areaPoints != null || areaHoles != null)
							{
								// Store path points in returned lists
								if (pathPointsClockwise ^ reversed)
								{
									currentPathPoints = (ArrayList<float[]>) currentPathPoints.clone();
									Collections.reverse(currentPathPoints);
									currentPathPoints.toArray(areaPartPoints);
								}
								if (pathPointsClockwise)
								{
									if (areaHoles != null)
									{
										areaHoles.add(areaPartPoints);
									}
								}
								else
								{
									if (areaPoints != null)
									{
										areaPoints.add(areaPartPoints);
									}
								}
							}
						}
					}
					break;
			}
		}
		
		List<float[][]> areaPointsWithoutHoles = new ArrayList<float[][]>();
		if (areaHolesLists.isEmpty() && areaPoints != null)
		{
			areaPointsWithoutHoles.addAll(areaPoints);
		}
		else if (areaPointsLists.isEmpty() && !areaHolesLists.isEmpty())
		{
			if (areaHoles != null)
			{
				areaHoles.clear();
			}
		}
		else
		{
			// Sort areas from larger areas to smaller ones included in larger ones
			List<List<float[]>> sortedAreaPoints;
			Map<List<float[]>, Area> subAreas = new HashMap<List<float[]>, Area>(areaPointsLists.size());
			if (areaPointsLists.size() > 1)
			{
				sortedAreaPoints = new ArrayList<List<float[]>>(areaPointsLists.size());
				for (int i = 0; !areaPointsLists.isEmpty();)
				{
					List<float[]> testedArea = areaPointsLists.get(i);
					int j = 0;
					for (; j < areaPointsLists.size(); j++)
					{
						if (i != j)
						{
							List<float[]> testedAreaPoints = areaPointsLists.get(j);
							Area subArea = subAreas.get(testedAreaPoints);
							if (subArea == null)
							{
								subArea = new Area(
										getShape(testedAreaPoints.toArray(new float[testedAreaPoints.size()][])));
								// Store computed area for future reuse 
								subAreas.put(testedAreaPoints, subArea);
							}
							if (subArea.contains(testedArea.get(0)[0], testedArea.get(0)[1]))
							{
								break;
							}
						}
					}
					if (j == areaPointsLists.size())
					{
						areaPointsLists.remove(i);
						sortedAreaPoints.add(testedArea);
						i = 0;
					}
					else if (i < areaPointsLists.size())
					{
						i++;
					}
					else
					{
						i = 0;
					}
				}
			}
			else
			{
				sortedAreaPoints = areaPointsLists;
			}
			for (int i = sortedAreaPoints.size() - 1; i >= 0; i--)
			{
				List<float[]> enclosingAreaPartPoints = sortedAreaPoints.get(i);
				Area subArea = subAreas.get(enclosingAreaPartPoints);
				if (subArea == null)
				{
					subArea = new Area(
							getShape(enclosingAreaPartPoints.toArray(new float[enclosingAreaPartPoints.size()][])));
					// No need to store computed area because it won't be reused 
				}
				List<List<float[]>> holesInArea = new ArrayList<List<float[]>>();
				// Search the holes contained in the current area part
				for (List<float[]> holePoints : areaHolesLists)
				{
					if (subArea.contains(holePoints.get(0)[0], holePoints.get(0)[1]))
					{
						holesInArea.add(holePoints);
					}
				}
				
				while (!holesInArea.isEmpty())
				{
					// Search the closest points in the enclosing area and the holes
					float minDistance = Float.MAX_VALUE;
					int closestHolePointsIndex = 0;
					int closestPointIndex = 0;
					int areaClosestPointIndex = 0;
					for (int j = 0; j < holesInArea.size() && minDistance > 0; j++)
					{
						List<float[]> holePoints = holesInArea.get(j);
						for (int k = 0; k < holePoints.size() && minDistance > 0; k++)
						{
							for (int l = 0; l < enclosingAreaPartPoints.size() && minDistance > 0; l++)
							{
								float distance = (float) Point2D.distanceSq(holePoints.get(k)[0], holePoints.get(k)[1],
										enclosingAreaPartPoints.get(l)[0], enclosingAreaPartPoints.get(l)[1]);
								if (distance < minDistance)
								{
									minDistance = distance;
									closestHolePointsIndex = j;
									closestPointIndex = k;
									areaClosestPointIndex = l;
								}
							}
						}
					}
					// Combine the areas at their closest points
					List<float[]> closestHolePoints = holesInArea.get(closestHolePointsIndex);
					if (minDistance != 0)
					{
						enclosingAreaPartPoints.add(areaClosestPointIndex,
								enclosingAreaPartPoints.get(areaClosestPointIndex));
						enclosingAreaPartPoints.add(++areaClosestPointIndex, closestHolePoints.get(closestPointIndex));
					}
					List<float[]> lastPartPoints = closestHolePoints.subList(closestPointIndex,
							closestHolePoints.size());
					enclosingAreaPartPoints.addAll(areaClosestPointIndex, lastPartPoints);
					enclosingAreaPartPoints.addAll(areaClosestPointIndex + lastPartPoints.size(),
							closestHolePoints.subList(0, closestPointIndex));
					
					holesInArea.remove(closestHolePointsIndex);
					areaHolesLists.remove(closestHolePoints);
				}
			}
			
			for (List<float[]> pathPoints : sortedAreaPoints)
			{
				if (reversed)
				{
					Collections.reverse(pathPoints);
				}
				areaPointsWithoutHoles.add(pathPoints.toArray(new float[pathPoints.size()][]));
			}
		}
		
		return areaPointsWithoutHoles;
	}
}
